feat: support custom library paths in react-native.config.js for codegen on iOS (#34580)

Summary:
Currently for codegen to work for a library on iOS, it needs to be located
inside `node_modules`. This patch adds support for libraries defined in
`react-native.config.js`.

This is useful when developing libraries as well as monorepos where the library
may exist outside of the `node_modules`.

Example:

```js
// react-native.config.js
const path = require('path');

module.exports = {
  dependencies: {
    'react-native-library-name': {
      root: path.join(__dirname, '..'),
    },
  },
};
```

## Changelog

[Internal] [Added] - Support custom library paths in `react-native.config.js` for codegen on iOS

Pull Request resolved: https://github.com/facebook/react-native/pull/34580

Test Plan:
Tested on a test application and ensured that codegen finds the library specified in `react-native.config.js`

https://user-images.githubusercontent.com/1174278/188141056-bce03730-2a13-4648-8889-9727aaf2c3c4.mp4

I have also added a basic test case for this scenario.

Reviewed By: jacdebug, cortinico

Differential Revision: D39257919

Pulled By: cipolleschi

fbshipit-source-id: 131189f1941128a59b9b1e28af61a9038eb4536b

scripts/codegen/__tests__/generate-artifacts-executor-test.js

@@ -13,13 +13,20 @@
 const underTest = require('../generate-artifacts-executor');
 const fixtures = require('../__test_fixtures__/fixtures');
 const path = require('path');
+const fs = require('fs');
+const child_process = require('child_process');
 
 const codegenConfigKey = 'codegenConfig';
 const reactNativeDependencyName = 'react-native';
 const rootPath = path.join(__dirname, '../../..');
 
 describe('generateCode', () => {
-  it('executeNodes with the right arguents', () => {
+  afterEach(() => {
+    jest.resetModules();
+    jest.resetAllMocks();
+  });
+
+  it('executeNodes with the right arguments', () => {
     // Define variables and expected values
     const iosOutputDir = 'app/ios/build/generated/ios';
     const library = {config: {name: 'library', type: 'all'}};
@@ -32,46 +39,32 @@ describe('generateCode', () => {
     const tmpOutDir = path.join(tmpDir, 'out');
 
     // mock used functions
-    let mkdirSyncInvocationCount = 0;
-    jest.mock('fs', () => ({
-      mkdirSync: (location, config) => {
-        if (mkdirSyncInvocationCount === 0) {
-          expect(location).toEqual(tmpOutDir);
-        }
-        if (mkdirSyncInvocationCount === 1) {
-          expect(location).toEqual(iosOutputDir);
-        }
-
-        mkdirSyncInvocationCount += 1;
-      },
-    }));
-
-    let execSyncInvocationCount = 0;
-    jest.mock('child_process', () => ({
-      execSync: command => {
-        if (execSyncInvocationCount === 0) {
-          const expectedCommand = `${node} ${path.join(
-            rnRoot,
-            'generate-specs-cli.js',
-          )} \
-        --platform ios \
-        --schemaPath ${pathToSchema} \
-        --outputDir ${tmpOutDir} \
-        --libraryName ${library.config.name} \
-        --libraryType ${libraryType}`;
-          expect(command).toEqual(expectedCommand);
-        }
-
-        if (execSyncInvocationCount === 1) {
-          expect(command).toEqual(`cp -R ${tmpOutDir}/* ${iosOutputDir}`);
-        }
-
-        execSyncInvocationCount += 1;
-      },
-    }));
+    jest.spyOn(fs, 'mkdirSync').mockImplementation();
+    jest.spyOn(child_process, 'execSync').mockImplementation();
 
     underTest._generateCode(iosOutputDir, library, tmpDir, node, pathToSchema);
-    expect(mkdirSyncInvocationCount).toBe(2);
+
+    const expectedCommand = `${node} ${path.join(
+      rnRoot,
+      'generate-specs-cli.js',
+    )}         --platform ios         --schemaPath ${pathToSchema}         --outputDir ${tmpOutDir}         --libraryName ${
+      library.config.name
+    }         --libraryType ${libraryType}`;
+
+    expect(child_process.execSync).toHaveBeenCalledTimes(2);
+    expect(child_process.execSync).toHaveBeenNthCalledWith(1, expectedCommand);
+    expect(child_process.execSync).toHaveBeenNthCalledWith(
+      2,
+      `cp -R ${tmpOutDir}/* ${iosOutputDir}`,
+    );
+
+    expect(fs.mkdirSync).toHaveBeenCalledTimes(2);
+    expect(fs.mkdirSync).toHaveBeenNthCalledWith(1, tmpOutDir, {
+      recursive: true,
+    });
+    expect(fs.mkdirSync).toHaveBeenNthCalledWith(2, iosOutputDir, {
+      recursive: true,
+    });
   });
 });
 
@@ -202,6 +195,83 @@ describe('extractLibrariesFromJSON', () => {
   });
 });
 
+describe('findCodegenEnabledLibraries', () => {
+  const mock = require('mock-fs');
+  const {
+    _findCodegenEnabledLibraries: findCodegenEnabledLibraries,
+  } = require('../generate-artifacts-executor');
+
+  afterEach(() => {
+    mock.restore();
+  });
+
+  it('returns libraries defined in react-native.config.js', () => {
+    const projectDir = path.join(__dirname, '../../../../test-project');
+    const baseCodegenConfigFileDir = path.join(__dirname, '../../..');
+    const baseCodegenConfigFilePath = path.join(
+      baseCodegenConfigFileDir,
+      'package.json',
+    );
+
+    mock({
+      [baseCodegenConfigFilePath]: `
+      {
+        "codegenConfig": {}
+      }
+      `,
+      [projectDir]: {
+        app: {
+          'package.json': `{
+            "name": "my-app"
+          }`,
+          'react-native.config.js': '',
+        },
+        'library-foo': {
+          'package.json': `{
+            "name": "react-native-foo",
+            "codegenConfig": {
+              "name": "RNFooSpec",
+              "type": "modules",
+              "jsSrcsDir": "src"
+            }
+          }`,
+        },
+      },
+    });
+
+    jest.mock(path.join(projectDir, 'app', 'react-native.config.js'), () => ({
+      dependencies: {
+        'react-native-foo': {
+          root: path.join(projectDir, 'library-foo'),
+        },
+        'react-native-bar': {
+          root: path.join(projectDir, 'library-bar'),
+        },
+      },
+    }));
+
+    const libraries = findCodegenEnabledLibraries(
+      `${projectDir}/app`,
+      baseCodegenConfigFileDir,
+      `package.json`,
+      'codegenConfig',
+    );
+
+    expect(libraries).toEqual([
+      {
+        library: 'react-native',
+        config: {},
+        libraryPath: baseCodegenConfigFileDir,
+      },
+      {
+        library: 'react-native-foo',
+        config: {name: 'RNFooSpec', type: 'modules', jsSrcsDir: 'src'},
+        libraryPath: path.join(projectDir, 'library-foo'),
+      },
+    ]);
+  });
+});
+
 describe('delete empty files and folders', () => {
   beforeEach(() => {
     jest.resetModules();

scripts/codegen/generate-artifacts-executor.js

@@ -204,6 +204,55 @@ function handleThirdPartyLibraries(
   });
 }
 
+function handleLibrariesFromReactNativeConfig(
+  libraries,
+  codegenConfigKey,
+  codegenConfigFilename,
+  appRootDir,
+) {
+  const rnConfigFileName = 'react-native.config.js';
+
+  console.log(
+    `\n\n[Codegen] >>>>> Searching for codegen-enabled libraries in ${rnConfigFileName}`,
+  );
+
+  const rnConfigFilePath = path.join(appRootDir, rnConfigFileName);
+
+  if (fs.existsSync(rnConfigFilePath)) {
+    const rnConfig = require(rnConfigFilePath);
+
+    if (rnConfig.dependencies != null) {
+      Object.keys(rnConfig.dependencies).forEach(name => {
+        const dependencyConfig = rnConfig.dependencies[name];
+
+        if (dependencyConfig.root) {
+          const codegenConfigFileDir = path.resolve(
+            appRootDir,
+            dependencyConfig.root,
+          );
+          const configFilePath = path.join(
+            codegenConfigFileDir,
+            codegenConfigFilename,
+          );
+          const pkgJsonPath = path.join(codegenConfigFileDir, 'package.json');
+
+          if (fs.existsSync(configFilePath)) {
+            const pkgJson = JSON.parse(fs.readFileSync(pkgJsonPath));
+            const configFile = JSON.parse(fs.readFileSync(configFilePath));
+            extractLibrariesFromJSON(
+              configFile,
+              libraries,
+              codegenConfigKey,
+              pkgJson.name,
+              codegenConfigFileDir,
+            );
+          }
+        }
+      });
+    }
+  }
+}
+
 function handleInAppLibraries(
   libraries,
   pkgJson,
@@ -362,6 +411,39 @@ function createComponentProvider(
   }
 }
 
+function findCodegenEnabledLibraries(
+  appRootDir,
+  baseCodegenConfigFileDir,
+  codegenConfigFilename,
+  codegenConfigKey,
+) {
+  const pkgJson = readPackageJSON(appRootDir);
+  const dependencies = {...pkgJson.dependencies, ...pkgJson.devDependencies};
+  const libraries = [];
+
+  handleReactNativeCodeLibraries(
+    libraries,
+    codegenConfigFilename,
+    codegenConfigKey,
+  );
+  handleThirdPartyLibraries(
+    libraries,
+    baseCodegenConfigFileDir,
+    dependencies,
+    codegenConfigFilename,
+    codegenConfigKey,
+  );
+  handleLibrariesFromReactNativeConfig(
+    libraries,
+    codegenConfigKey,
+    codegenConfigFilename,
+    appRootDir,
+  );
+  handleInAppLibraries(libraries, pkgJson, codegenConfigKey, appRootDir);
+
+  return libraries;
+}
+
 // It removes all the empty files and empty folders
 // it finds, starting from `filepath`, recursively.
 //
@@ -429,23 +511,12 @@ function execute(
   }
 
   try {
-    const pkgJson = readPackageJSON(appRootDir);
-    const dependencies = {...pkgJson.dependencies, ...pkgJson.devDependencies};
-    const libraries = [];
-
-    handleReactNativeCodeLibraries(
-      libraries,
-      codegenConfigFilename,
-      codegenConfigKey,
-    );
-    handleThirdPartyLibraries(
-      libraries,
+    const libraries = findCodegenEnabledLibraries(
+      appRootDir,
       baseCodegenConfigFileDir,
-      dependencies,
       codegenConfigFilename,
       codegenConfigKey,
     );
-    handleInAppLibraries(libraries, pkgJson, codegenConfigKey, appRootDir);
 
     if (libraries.length === 0) {
       console.log('[Codegen] No codegen-enabled libraries found.');
@@ -482,6 +553,7 @@ module.exports = {
   execute: execute,
   // exported for testing purposes only:
   _extractLibrariesFromJSON: extractLibrariesFromJSON,
+  _findCodegenEnabledLibraries: findCodegenEnabledLibraries,
   _executeNodeScript: executeNodeScript,
   _generateCode: generateCode,
   _cleanupEmptyFilesAndFolders: cleanupEmptyFilesAndFolders,